Bug fixes:

• re-work, document and test Imager's logging facility. RT #65227
• fix META.yml testing and the generated META.yml RT #65235
• test and add error reporting to to_*() family methods
• add to_rgb_double() method. RT #65101
• Imager no longer exports anything by default RT #65228
• convert colors to grayscale if the supplied (or generated) palette contains only grays when performing error diffusion color translation. RT #68508
• writing a paletted image to GIF wouldn't always use the colors supplied (or generated, eg. via make_colors => "mono"), which was confusing at best. RT #67912
• replace (imager|tony)@imager.perl.org in the doc, since I don't plan to continue receiving mail at that address. RT #68591